Recently, it has been found that an antibody (or antibody fragment such as a single-chain variable fragment) can be linked to a payload drug to form an immunoconjugate that has been termed antibody-drug conjugate, or ADC. The antibody causes the ADC to bind to the target cells. Often the ADC is then internalized by the cell and the drug is released to treat the cell. Because of the targeting, the side effects may be lower than the side effects of systemically administering the drug.